Likely simple Ms. Pac Question

wontwa

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I've done a bunch of reading and haven't found the answer to this specifically so thought I'd post here. I recently purchased a non-working Ms. Pac cocktail - monitor glows, coin door and lights near joysticks light up, speaker hums but that's it. Reseated all of the chips, wiggled edge connector and nothing. I went ahead and purchased an Arcadeshop power switcher as that fixed my Galaga that had similar symptoms. After a lot of reading I realize that I could have probably just installed new fuse holders, but I don't really feel like going to the trouble of returning the switcher at this point.

There were no instructions included with the switcher, so these are the questions I have:

1) is there a preferred spot to connect the switcher to 115 (I did see info about this pretty extensively in a different thread but didn't really see a definitive answer)?

2) what exactly do I need to disconnect/desolder from the power block at the bottom of the cocktail in order to use the switcher (assuming that I have the switcher hooked into the 115 and connected to the board)? If anything?

3) as you can see in the pictures, it appears someone has done some hack job with what I think may be power to the board (basing this on the fact that the colors of red, orange and black are the same type the switcher uses). Should I de-solder this from the board and the harness and use some electrical tape to return the harness wiring to it's original state?

(I'm planning on putting the fuses back in, those happened to be removed at the time of photo)

Thanks for any help!!!!
 

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1) is there a preferred spot to connect the switcher to 115 (I did see info about this pretty extensively in a different thread but didn't really see a definitive answer)?

A: I would use the 115/OV tabs on the input side of the larger transformer.

2) what exactly do I need to disconnect/desolder from the power block at the bottom of the cocktail in order to use the switcher (assuming that I have the switcher hooked into the 115 and connected to the board)? If anything?

A: Nothing really, just leave out the fuses in the 4 position block. You can solder your switcher power right to the fuse holder tabs on the harness side of the 4 position block.

3) as you can see in the pictures, it appears someone has done some hack job with what I think may be power to the board (basing this on the fact that the colors of red, orange and black are the same type the switcher uses). Should I de-solder this from the board and the harness and use some electrical tape to return the harness wiring to it's original state?

A: That looks like someones way of bypassing the edge connector thats burned up.
 
Thanks for the reply and all of the info. I was in mid-fuse block replacement when you replied (in case all else failed), and since it was awkward soldering at that angle with the monitor open, finished what I was doing and went ahead and soldered the switcher to the harness side of fuse block as shown (the two red wires coming in).

Hooked the switcher back up and not only is there no power on the switcher, but the speaker hum, the lights by the joysticks, and the coin door lights no longer light up. The fan in the bottom of the cab and the monitor still power up, however. Guessing I should look for the 115/OV tabs on the input side of the larger transformer?

Attached photos are what I just did, and how I have the switcher wiring hooked up to the +5 just to make sure that's accurate (2 reds to the +5, to black to ground, orange to +12).

Thanks again!
 

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Thats not right. Hook the switchers AC wires to the 115 & 0V lugs on the transformer. The switcher +5 output needs to go to the two fuse lugs marked 7v. The switcher +12 output needs to go to the two fuse lugs marked 12v. The switcher ground needs to be tied in to the yellow/grn wire somewhere. The easiest place is probably the solder lug that is on one of the transformer mounting bolts.
 
Thank you for the more detailed response. Realized I left out the part that mentions that the switcher came with one of those handy adapter deals (image attached).

Attached the 115 wires from the switcher to the two bottom posts on the transformer (9v and 115) and while the light on the power switcher finally lit up red for a change....that was it. Didn't realize the one on the lower left said 9v until I saw the picture I was about to post here with flash and was able to reinvestigate.

Tried soldering both of the red 115 from the switcher to the 115 post on the transformer - and nothing at all. I can't tell what the blue and yellow wire(s) at the top is/are attached to, is that the 0v? Unsoldered the switcher entirely and just put the fuses back into the new fuse tray, and it was the same as it originally was - minus the lights by the joysticks - so looks like I'm rechecking my handiwork there.

Pretty frustrating, I feel like I'm thiiiiiis close. A greater understanding of electricity in general would probably help me out here.

Thanks for your time. If anyone could tell me if that top post that the blue/yellow wire is attached to is the 0v that would be a huge help.
 

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well..

even though it worked with 9 volt batteries don't lick the ends of the wires to see if their hot! :) LOL
Pretty frustrating, I feel like I'm thiiiiiis close. A greater understanding of electricity in general would probably help me out here.
 
Yeah, I think the blue with yellow stripe is neutral (0v). Look at the label on the transformer, it should say right on it.
 
Sorry I skipped this thread. The easiest way to tap into the 120 for the switcher is at the input to the isolation transformer. It only has four wires - two on the bottom (input) and two on the top (output). Connect a wire to each lug on the bottom, and then connect those wires to the AC input lugs of the switcher. Done.

You could connect it to the output lugs, too, but then you may get monitor interference if the switcher ever starts to fail...
 
Thanks for the advice - this isn't working out for some reason, so if you don't mind a couple more questions:

1) in the picture above that I posted of the switcher, do I have the wires connected to the posts of the switcher properly? - i.e. are both of those red wires supposed to be connected to that top +5 post, or should one of them be connected to the -5?

The reason I ask is that if I move one to the +5 and one to the -5, no red light on the switcher turns on but I hear that whirring/clicking type noise inside of the switcher that indicates that it's trying to do something (based upon my experience with the Galaga switcher - which came with a post adapter so I can't really use that for comparison). If I have them both on +5, the red light of the switcher turns on, but no sound or anything indicating the switcher is doing anything.

2) I have no fuses in the 4 post holder presently, could this be the reason nothing's happening? Can I put them back in without fear of messing up the switcher or could I ruin it? If nothing else, I feel that I should put them in in order to get my lights by the joysticks to turn back on (they haven't been on since I've removed the fuses due to above advice).
 
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